Sample-rate conversion (SRC) is the process of changing a sampling rate of a discrete signal to obtain a new discrete representation of the underlying continuous signal. A typical SRC implements a rational re-sampling ratio M/N. M is a first sample rate, for instance an up-sampling rate, and N is a second sample rate, for instance a down-sampling rate. Up-sampling, or interpolation, increases a sampling rate of a signal. Down-sampling, or decimation, decreases the sampling rate of the signal.
Signal chain systems such as communications transceivers and automotive radar receivers use M/N SRC. In those applications, high-performance, RF-sampling ADCs with integrated digital front-ends implement the M/N SRC. In mobile network base stations, the front-ends may change the ADC sampling frequency in a range of, for instance, 2 GHz to 3 GHz depending on the center frequencies of signal bands. That technique prevents second and third harmonic spurs from folding back in to the signal bands. However, interface rates for decimated input signals may be at fixed sample rates, for instance 245.76 MHz, which may necessitate resampling factors of 8/9, 4/5, and 2/3.